Dry-pan crusher



Aprll 26, 1927- 5. F'owLER DRY PAN CRUSHER' Filed Dec. 19

ATTORNEY Patented Apr. 26, 1927.

UNITED STATES PATENT OFFICE.

JOHN S. FOWLER, OF SAN MATEO, CALIFORNIA, .ASSIGNOR TO PACIFIC FOUNDRYCOM- ZIP-ANY, OF SAN FRANCISCO, CALIFORNIA, A GOEEQI't-A'EIQN OFCALIFORNIA.

DRY-PAN CBUSHER.

Application filed December 5, 1925.

My invention relates to crushing machines of the type known as dry panmachines, and which are principally used for grinding or pulverizinaclay in a dry state, for use in making brick, pottery, or other clayproduct-s.

The principal object of my invention is to provide an improved screenplate for machines of the described type, which is less subiect tobreakage than the screen plates now in common use. and which is soconstructed that it can be easily replaced, sectionilly, when worn,without necessitating the scrapping of the entire plate to eliminate aworn portion of relatively small area.

Other objects and advantages of my invention will be apparent from thefollowing description of a preferred embodiment thereof, which should beread with the understanding that the form. proportion, and arrangementof the several parts of the device may be varied, within the limits ofthe claims hereto appended, without departing from the spirit of theinvention as set forth in said claims.

With this in view a preferred embodiment of my invention will now bedescribed fully with reference to the accompanying drawings, wherein sFig. 1 is a part sectional front elevation of the complete machine.

Fig. 2 is a part sectional and partly broken plan view of the revolvingpan.

Fig. 3 is a plan view, enlarged, of one of my improved screen platesegments.

Fig. 4 is a bottom view of the same.

Fig. 5 is a sectional. detail of one of the connections between adjacentscreen plate sections. 7

In the drawings, and referring; for the moment to Fig. 1 thereof, thereference numeral 1 designates a frame, in the upper portion of which isiournaled a horizontal drive shaft 2 provided with means, as for examplea pulley 3, for receiving power from an outside source. not shown. Theshaft 1 drives, by means of bevel nears 4,

a vertical shaft 5, the lower end of which runs in a suitable-stepbearing indicated at 6. This vertical shaft 5 carries apan 7, into whichthe clay or other l'naterial is 1ntroduced, by any suitable means notshown,

and in which said material is ground by rollers 8, there being two suchrollers rotatively carried upon a stationary horizon- Serial No. 73,419.

in] shaft 9 suitabl" secured in the frame 1.

The pan 7 as shown in Fig. 2, comprises a hub 10 secured upon thevertical shaft 5, and a frame secured to said hub and made up of radialmembers 11 and an annular member 12. Upon said frame rests a flat floorcomprising a series of sections. The inner portion of said floor, uponwhich the rollers 8 run, is solid, and is formed of a series ofsegmental plates 13 resting upon the frame members 11 and 12 and secured thereto by any suitable means, not

shown. The outer portion of said floor is perforate, and is formed of aseries of segmental screen plates 14, one of which is shown in detail inFigs. 3 and 4. A flange or rim 15, Figs. 1 and 2, extends around theperiphery of the pan, and is secured to the ends of the frame arms 11.

An angularly disposed scraper 16, Figs. 1 and 2. is adjustably mounted,by means of a suitable bracket 17, upon a fixed bar 18, and overlies thescreen plates 14. As a the pan revolves, the material is crushed betweenthe rollers 8 and the solid plate por tions 13, andis thrown toward theperiphery of said pan by centrifugal force. The finer portions of thematerial drop through the perforations of the screen plates 14 to anysuitable place of deposit, not shown, and the remainder is worked backto the rollers 8 by the scraper 16. Thus the grind ing is continueduntil all of the material .is fine enough to press through saidperforations.

The present invention resides in the screen plates 14 and the partsclosely associated therewith. As shown in Figs. 2, 3 and 4, I make saidplates of a plurality of arcuate concentric sections, there being threesuch sections,14 14 and 14, in the form shown in the drawings, in eachsegmental plate. Each such section is provided upon its under surfacewith a marginal flange or rib 19, Fig. 4, adapted to rest upon the panframe members 11 and 12, and the three sections comprising; eachsegmental plate are preferably connected together by bolts 20 passingthrough slots 21' in lugs 21 formed at suitable points upon saidflanges, as shown in Figs. 4 and 5. To further strenghten theconnections between adjacent sections, I prefer to employ a pair ofslotted steel plates 22 lying beneath the head and the nut,respectively, of each bolt 20, and the outer ends of said plates aredrawn together by a second bolt 23 to increase the clamping effectproduced by the bolt 20. Thus the three sections 14, 14 and 14;", arefirmly united to form a segmental plate 14. and said plate rests uponthe pan arms 11. and is preferably secured thereto by bolts .24, Fig. 2,passing through suitable holes 24:. Figs. 3 and l in said plate. Thesurface of the screen plates is preferably flush with the surfaceof thesolid crushing plates 13.

Each arcuatc screen plate section is perforated by arcuate slots 25.Figs. 3 and l, of suitable width. The slots 2 and also the joints 26between adjacent sections are all concentric with the pan 7, so that, assaid pan revolves, any given slot or any given joint will. follow a truecircular path about the axis of the shaft 5 as a center.

The scraper 16 is preferably provided with three removable blades orsections 16", 16 and 16, Figs. 1 and 2. corresponding in position to thethree screen plate sections 14", 14. and 14. These blades are preferablyindependently adjustable. vertically, upon the scraper 16, and are heldthereon by any suitable means, not shown in the drawings' I am awarethat screen plates of the described type have been constructed insegmental form. and that such segmental plates have been divided intosect-ions by tangential straight-line joints; and I am also aware thatscreen plates have been perforated by slots arranged in straight lines,both radially and tangentially. Therefore, my invention residesessentially in the provision of a screen plate divided into sections byarcuate joints concentric with the pan of which they are a part, andperforated by arcuate slots likewise concentric with the pan. This formof screen plate produces important and advantageous results, when usedin machines of the described type, over the forms of screen plate now incommon use.

One such result is the localization of wear. The surface of screenplates in machines of the type described is subject to wear caused bythe abrading action of the material passing under or catching upon theedge of the scraper, and such wear occurs unevenly over the surface ofthe plate because of the fact that. once a worn area of limited extentappears, the wear in that area proceeds with greater rapidity than inother portions of the plate on account of the relatively greater spacebetween the scraper and the surface of the worn area, and the consequentgreater abrading action of the material passing thereunder. However,such worn areas are roughly arcuatc in outline, and concentric with thepan. Now it a screen plate segment is not divided into sections. theentire segment must be replaced to eliminate arelatively small worn are:whereas in my arcuate concentric sectional construction, the worn area,in a great majority ol cases, is confined to one section, so that thatsection only need be replaced. Moreover, there is much more likelihoodthat a. worn area will be confined to one section in my arcuatecouslruclion in which the segments have the same. general(mi'lfiguration as the worn areas, than in the case o'l segmeiit-sdivided into sections along tangential straight lines.

The arcuate screen plate sections also no operate with the sectionalscraper blades 16", 16 and 16, so that it any one annular series oilscreen sections wear more rapidly than the others, the scraper bladeoperatingover such worn sections can be adjusted indcpendently of theother blades.

The connections between adjacent screen plate sections, formed by thebolts 20 passing through the slots 21 ot the lugs 21, proride for alimited relative adjustmentot said sections. so that if one sectionwears more rapidly than its neighbors. it can be raised slightly toagain bring its surface lush with that of the surrounding sections, theslots 21 permitting such relative adj ustment. These slotted connectionsare also useful in permittin adjustment to compensate tor slightvariations in the thickness of new plates, or to adjust a new sectionflush with adjacent slightly worn sections. As shown in Fig. 5, the lugs21 are made long enough to carry the slots 21 without having to make theflange 19 unduly wide.

Another advantageous result of my construction lies in the practicalelimination of Such breakage breakage of screen plates. occurs in plateshaving radial or tangential slots and is caused by a hard lump ofmaterial becoming caught or wedged in a slot, and when such a wedgedlump is. struck by the scraper, a force is set up which has a componentat right angles to the length of the bar or band separating the slot inquestion from the next succcedin slot. Such a force may, and very oftendoes, break the bar, thus necessitating the replacement of the plate orsection. In my arcuately and concentrically slotted plate, however, theslots lie along the path of travel of the scraper, instead of acrossvit, so that..when a wedged lump is struck, the force occurs almostentirely in the direction ot the length of the slot, and nottransversely of the bars. The very slight transverse component due tothe angularity of the scraper is not sufficicnt to cause breakage. Iclaim 1. In a dry pan crusher, a pan comprising a frame: an annularscreen plate adapted to rest upon said frame, said plate being dividedby radially disposed joints into a plurality of segments. and eachsegment being divided into sections by arcuate joints concentric withthe pan; depending marginal flanges formed upon the arcuate edges ofeach section; and separable connections between the adjacent flanges ofthe sections of each segment, each connection comprising a boltextending through the two adjacent flanges, a pair of clai'nping plaleshaving their upper ends respectively clamped against said flanges hy thehead and the nut of said bolt, and a second bolt extending through andbinding; together the lower ends of said plates.

2. In a dry pan crusher, a pan comprising a frame; an annular screenplate adapted to rest upon said frame, said screen plate being dividedinto a plurality of sections; depending marginal flanges at the edges ofand integral with said sections; and means comprising bolts passingthrough slots in said flanges for separably connecting together saidsections, and adapting them for relative vertical adjustment.

3. In a dry pan crusher, a pan comprising a frame; an annular screenplate adapt ed to rest upon said frame, said screen plate being dividedinto a plurality of sections; depending marginal flanges at the edges ofand integral with said sections; lugs formed with, and longer than thewidth of, said flanges, said lugs having slots therein; and boltspassing through said slotted lugs for separably connecting together saidsections and adapting them for relative vertical adjustment.

4t. In a dry pan crusher, a pan comprising a frame; an annular screenplate adapted to rest upon said frame, said screen plate being dividedinto a plurality of sections; depending marginal flanges at the edges ofand in tegral with said sections; bolts passing through slots in saidflanges, for separably connecting said sections v together and adaptingrthem tor relative vertical adjustment, and a pair of clampingplatesassociated at one end with said bolts and bolted together at their otherends.

In testimony whereof I have signed my name to this specification.

JOHN S. FOWLER.

